This invention relates to an assembly for clamping tube plates in heat exchangers.
The technical field of heat exchangers is known to comprise a large variety of designs wherein a tube plate is arranged to bear, with the interposition of a gasket, on a surface suitably formed on the shell end, and is clamped in that position to sealingly separate the fluid flown through the tube interiors and the fluid which sweeps the tube exteriors in flowing through the space portion enclosed by the shell.
The devices for clamping the tube plate are quite numerous in the art, such as, to name but a few, a device which includes a plurality of stud bolts arranged around the gasket and adapted to be engaged with holes provided in the tube plate which is tightened down by means of nuts, or the one including a ring which is inserted into a peripheral grove of the tube plate, wherewith braces are associated which engage with a second ring overlying the peripheral area of said tube plate so as to compress it onto said gasket by tightening nuts provided at the brace ends.
The disadvantages of prior devices, among which the not negligible one of excessive space requirements in the radial direction as is evidenced by the cited examples, have induced the Applicant to provide a device which comprises a ring inserted into a circumferential groove formed in the thickness of the header portion at a position overlying the tube plate, and being provided, within the reach of the annular portion thereof projecting beyond said groove, with a means effective to press the underlying tube plate against the sealing gasket.
For its insertion into the circumferential grove, the ring is fabricated in plural segments which, of course, must be held in place, and this problem is solved, in the cited device, through the use of a unitary construction retaining ring which is inserted within the segmented ring on the opposite side to that facing the tube plate.
The device just described has shown to be of considerable value and advantageous; however, the actual experience made with the device and continued study directed to impart it with increasingly better characteristics have enabled the provision of the improvements which this patent aims to protect.